module I18n::Backend::Gettext

def load_po(filename)
  locale = ::File.basename(filename, '.po').to_sym
  data = normalize(locale, parse(filename))
  [{ locale => data }, false]
end

def normalize(locale, data)
  data.inject({}) do |result, (key, value)|
    unless key.nil? || key.empty?
      key = key.gsub(I18n::Gettext::CONTEXT_SEPARATOR, '|')
      key, value = normalize_pluralization(locale, key, value) if key.index("\000")
      parts = key.split('|').reverse
      normalized = parts.inject({}) do |_normalized, part|
        { part => _normalized.empty? ? value : _normalized }
      end
      Utils.deep_merge!(result, normalized)
    end
    result
  end
end

def normalize_pluralization(locale, key, value)
  # FIXME po_parser includes \000 chars that can not be turned into Symbols
  key = key.gsub("\000", I18n::Gettext::PLURAL_SEPARATOR).split(I18n::Gettext::PLURAL_SEPARATOR).first
  keys = I18n::Gettext.plural_keys(locale)
  values = value.split("\000")
  raise "invalid number of plurals: #{values.size}, keys: #{keys.inspect} on #{locale} locale for msgid #{key.inspect} with values #{values.inspect}" if values.size != keys.size
  result = {}
  values.each_with_index { |_value, ix| result[keys[ix]] = _value }
  [key, result]
end

def parse(filename)
  GetText::PoParser.new.parse(::File.read(filename), PoData.new)
end